There exist many mechanisms for tightening shoes, boots, skates, and other footwear. Conventional mechanisms for tightening footwear range from simple manual lace tightening to more complex buckles or clamps and the like. Manual lace tightening has many drawbacks including, for example, difficulty in adjusting the lace tightness and uneven distribution of pressure from the tightening. Buckle and clamp style systems, while quicker than manual lace tightening, cause pressure points where the buckles or clamps exist. These pressure points cause localized hot spots and irritation, which can lead to blisters and the like.
VELCRO® straps can be used in place of buckles and/or laces, but they suffer many of the drawbacks of buckles in they produce localized pressure points and uneven tightness distribution. Further, the straps are prearranged, similar to buckles, inhibiting the shoe from free forming to a user's foot shape. The result is localized pressure points and hotspots that can irritate the foot.
An existing automatic lace tightening system is described by U.S. Pat. No. 6,289,558, issued Sep. 18, 2001, and U.S. Pat. No. 5,934,599, issued Aug. 10, 1999, both titled FOOTWEAR LACING SYSTEM, both issued to Hammerslag. The Hammerslag Patents describe a circular tightening apparatus that is rotated to tighten the laces and locked in place with a ratchet and pawl lock. The laces are loosened by releasing the lock by lifting the pawl and pulling on the laces to loosen them, or using reverse rotation of the ratchet. As can be seen, the Hammerslag Patents disclose a conventional shoe having an upper with an open throat. Opposing sides of the upper are tightened using the laces and tightening system of the Hammerslag Patents.
All of the above systems, are ways to tighten the throat or canopy of the shoe. While this is helpful, the shoes uppers still bind or develop local hotspots around the majority of the foot. In order to inhibit the formation of local hotspots or other irritating pressure points, multi-layer upper constructions are being developed. Referring to FIGS. 1 and 2, an upper 100 is shown. FIG. 1 shows an elevation view of upper 100 on a shoe and FIG. 2 shows a cross section of upper 100 exploded. Referring first to FIG. 1, upper 100 includes a series of loops or hooks 2, 4, 6, 8, and 10 on each side of upper 100. Loops 2, 4, 6, 8, and 10 have a top section 12 through which laces may be threaded. Loops 2, 4, 6, 8, and 10 also have a bottom section 14 typically attached at the upper sole junction 16. Thus the bottom is typically stitched, adhered, or fused in upper sole junction 16. As can be seen from FIG. 1, by threading the laces through top sections 12, when the laces are tightened about a shoe throat 18 (or gap), loops 2, 4, 6, 8, and 10 distribute the tightening substantially equally about the foot to prevent binding, hotspots, and other irritation.
Referring to FIG. 2, an exploded cross section of upper 100 is shown. Upper 100 comprises (from inside the shoe out) a backing layer 22, a mesh or breathable fabric layer 24, a bonding layer 26, a loop layer 28, and a topside layer 30. Optionally, another bonding layer 26 may exist between backing layer 22 and fabric layer 24 and between loop layer 28 and topside layer 29. Loops 6 and 8 are shown in loop layer 28. While FIG. 2 is not drawn to scale, one of ordinary skill in the art appreciates that constructing upper 100 this way reduces breathability, increases weight, reduces moisture management, and increases production time and cost, but is designed to increase comfort by distributing the effects of lace tightening around more of the foot.
Thus, it would be desirous to develop an improved fabric that would facilitate shoe tightening and inhibit the formation of hotspots or other irritants, but also increase breathability, increase moisture management, decrease weight, and decrease production costs and time.